Allow fine-tune planner steps

[waynexia]

Is your feature request related to a problem or challenge?

The planning phase generates and optimizes both logical and physical plans. IIRC we only provide one method to "optimize and create" a physical plan:

datafusion/datafusion/core/src/execution/session_state.rs

Lines 715 to 723 in a721be1

	pub async fn create_physical_plan(
	&self,
	logical_plan: &LogicalPlan,
	) -> datafusion_common::Result<Arc<dyn ExecutionPlan>> {
	let logical_plan = self.optimize(logical_plan)?;
	self.query_planner
	.create_physical_plan(&logical_plan, self)
	.await
	}

Describe the solution you'd like

There are two approaches to alleviate this:

• Expose more methods that each one only does one step, like create_logical_plan, analyze_logical_plan, optimize_logical_plan, create_physical_plan and optimize_physical_plan etc.
• Expose those components to users, like

    /// Returns the [`Analyzer`] for this session
    pub fn analyzer(&self) -> &Analyzer {
        &self.analyzer
    }

    /// Returns the [`Optimizer`] for this session
    pub fn optimizer(&self) -> &Optimizer {
        &self.optimizer
    }

    /// Returns the [`QueryPlanner`] for this session
    pub fn query_planner(&self) -> &Arc<dyn QueryPlanner + Send + Sync> {
        &self.query_planner
    }

Describe alternatives you've considered

No response

Additional context

No response